The present invention relates generally to a coupling between at least two highly stressed bodies, such as pipes, rings, disks, plates and similar articles, and more particularly to a coupling having centering means for maintaining alignment of the thermally stressed bodies.
In the case of known flanged joints between two pipes with different coefficients of thermal expansion which abut on the front side, axial clamping is effected by screws and clamping devices which are applied to flange surfaces of one or the other pipe in a plane determined by the abutting surfaces of the two pipes. Such an arrangement is disclosed in German DE-AS No. 11 86 703. In the case of an unequal thermal expansion of the two pipes, such a flanged connection prevents a separation and thus a leaking of the two pipes at the abutting surface.
However, in the case of a thermal expansion of the pipe which also takes place in radial direction, such a flanged connection cannot prevent the pipes from decentering. In some types of application, this causes considerable problems.
An objective of this invention is the provision of a coupling which prevents a decentering of the longitudinal axes of the bodies that are connected with one another, when a thermal expansion of the bodies takes place.
Another objective of this invention is the provision of coupling means adaptable to a wide variety of members to be coupled.
Yet another objective of the invention is the provision of a coupling which may be composed of several different materials having different coefficients of thermal expansion.
These and other objects of the present invention are achieved by providing each of two members to be coupled with a series of centering elements for preventing decentering of the two members during periods of thermal change. Inner and outer centering elements are provided on each member, each element having centering surfaces extending radially and transversely relative to contact surfaces of the members to be coupled. The centering elements of one member contact the centering elements of the other member only at their centering surfaces, thereby allowing for thermal expansion toward other surfaces of the elements without deformation of adjacent elements. Additional decentering arrangements are disclosed for coupling flat members. The couplings disclosed are particularly advantageous for coupling metal to ceramic.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawing.